Belt wrapper for a coiler for the winding of rolled steel strip



Jan. 28, 1969 G.SCHREIBER ETAL 3,423,981

. BELT WRAPPER FQR'A COILER FOR THE WINDING OF ROLLED STEEL STRIP Filed Sept. 20, 1966 Sheet of 2 lnvenzors GERHARD SCHREIBER 8- HERMANN KRAUS agqfl THEIR ATTORNEY Jan. 28, 1969 G. SCHREIBER ETAL 3,423,981 BELT WRAPPER FOR A COILER FOR THE WINDING OF ROLLED STEEL STRIP Filed Sept. 20, 1966 Sheet 3 of 2 Inventors GERHARD SCHREIBER a HERMANN KRAUS Q fl THEIR AT TORNEY United States Patent Office U.S. Cl. 72-148 Int. Cl. 1321c 47/10; 321d 5/14 9 Claims ABSTRACT OF THE DISCLOSURE This disclosure relates to a belt wrapper of the type employed for winding metallic strip on a reel, such as found in a plant for producing coils of strip. The belt wrapper disclosed comprises a frame which carries several belt guiding rollers. At least two of these rollers are carried by shafts which, in turn, are carried b pivotal arms. The shafts also carry pinch rolls, one of which is located to directly engage the strip at a point where the strips leading end initially contacts the reel. Immediately behind this pinch roll is a crescent-shaped guiding member which, in combination with the positive driving effect of the pinch roll, prebends and drives the strip around the reel.

The invention relates to a belt wrapper for winding hot or cold rolled steel strip on a reel or mandrel and particularly for a belt wrapper for winding thick cold rolled material. Such winding has been previously done, for example, by introducing the front end of the strip into a slot of the coiler drum and causing it to be folded down at the edges as the drum is started, so that the material is carried along by reason of the folded-down strip engaging positively the periphery of the mandrel. Such an inwardly bent strip, however, caused extreme difliculty in subsequently unwinding the coil by a mandrel. Attempts to rebend the folded-down strip are rather diflicult to perform and the cold deformation effected by such an attempt brings about increased hardness at the bending point and especially local strengthening of the material, which is sometimes referred to as a wart which makes further satisfactory processing of the rolled material diflicult or impossible.

Nor will the use of loose strip coilers bring any final solution because a strip wound by a loose coiler lacks sufficient tightness between the layers, so that individual convolutions of the coil remain laterally shiftable. To hold the leading end of thin cold reduced strip against the reel belt wrappers has proven satisfactory, which, during the initial windings of the reel, cause the strip to bear against its periphery. With heavier material, however, it has been found that the belts will not suflice to bring the leading end of the strip to bear against the mandrel. As a result the belts are forced away from the mandrel by the front end of the strip creating an irregular operation that forms a non-cylindrical inside of the finished coil and excessive wear of the belts. To eliminate these draw backs a suggestion has already been made to give the leading end of the strip a cylindrical shape according to the diameter of the mandrel and bring it with the preshaped portion into position around the mandrel. In carrying out this proposal special equipment is needed to preshape the leading end of the strip and to prevent the preshaped front end from bending back so that it is necessary to hold the latter against the mandrel, thereby endangering the continuity of the forward travel of the coiling material.

The above disadvantages in using belt wrappers for 3,423,981 Patented Jan. 28, 1969 gripping and pressing heavy gauge cold reduced material against the mandrel are avoided according to the present invention through the fact that in the zone where the belt or belts run up to the drum, the introduced strip material passes through pinch rolls bearing against the drum shell and subsequent thereto, guide elements are provided that correspond to the drum periphery. The pinch rolls generate a relatively high contact pressure in the zone of the tangential contact by the belts at which place the latter are unable to exert a normal force directed on the drum periphery. Thus, the pinch rolls assure the positive advance of the cold reduced strip. In addition the subsequently arranged passage formed between the guide elements and the drum shell brings about a deflection of the leading end and causes deformation of the leading end of the strip under the influence of a short lever arm, i.e., in the zone directly following the strip front end. The gap between the leading end of the strip and the mandrel is thereby limited to a harmless degree.

In addition thereto in certain cases it is advantageous to provide additional pinch rolls in the zone where the belt or belts run off the drum, which is assisted by the aid of a succeeding guide element hold the peripher of the strip safety within the range of the completed loop and guide it with a minimum distance from the mandrel beneath the further advancing rolled material. After this, the pinch rolls arranged ahead of the entry guide assure that the leading end of the strip is maintained against the mandrel.

For further protection of the belts, it may be advisable to arrange contact rollers and guide elements next to or between the belts. The pinch rolls which as noted, contact the strip are driven by the deflector rolls, which carry and are embraced by the belt which, in turn, are driven by the coiler drum, and for which purpose the two different rolls are carried by common shafts. The radii of the pinch rolls exceed that of the deflector rolls by about the thickness of the belt.

In the preferred form, the pressure or pinch rolls are mounted on lever arms which also carry guide and/or deflector rolls in addition to the entry or guide elements. In connection therewith, in order to obtain greater contact forces, it was found beneficial to locate the guide and/or deflector rolls so that they will have a greater lever elfect than that of the pinch rolls.

As to the guide element connected after the second pinch roll, it is recommended to locate the guide as far as possible towards the overlapping Zone of the strip material.

It has been found advantageous to limit the lift of the arms carrying the pinch rolls by means of adjustable stops.

The invention will be described hereunder in greater detail by referring to the following drawings representing an embodiment thereof, in which:

FIGURE 1 is a side elevation of a belt wrapper encompassing a coiler drum; and

'FIGURE 2 is a plan view on the top pinch or contact rolls.

FIGURE 1 represents a coiler drum 1 embraced by the belts of a belt wrapper shown in its operating position. Shown in a frame 2 of the belt wrapper is an upper roller arm 4 hinged to a pin 3 and a lower roller arm 6 hinged to a pin 5. The upper roller arm 4 shows the deflector rolls 7 and guide rolls 8; whereas, in the lower 'roller arm 6, the deflector rolls 9 and the guide rolls 10 are mounted. Also arranged in the frame 2 are tension rollers 11 which by means of the tension cylinder 12 can be hydraulically adjusted or tensioned. The rollers are arranged in pairs and two belts 13 are put around them. The frame 2 is guided shiftably in the U-rail 14 by means of rollers, not shown in the figure.

On the shaft carrying the guide rolls 8, fixedly connected with the latter, are mounted pinch rolls whose radii exceed that of the guide rolls by a little more than the belt thickness, so that the body surfaces of the pinch rolls protrude somewhat beyond the belt surface. In a similar way, on the shaft carrying the deflector rolls 9, three pinch rolls 16 are arranged whose body surface next to and between the belts 13 protrudes beyond the latters surface. Connected rearwardly of the pinch rolls 15 are guide elements 17 which in the starting position are governed by a stop of the upper roller arms 4 and form with the shell of the drum a passage whose clearance exceeds the thickness of the strip material to be coiled. Connected to the inside of the pinch rolls -16 are guide elements 18. As seen in the rotary direction of the strip head end, entry elements 19 are arranged ahead of the pinch roll 16 between the lower roller arms 6, which lead the leading end of the entering strip safely and without jerks beneath the pinch roll. The normal position of the lower roller arm 6 is likewise determined by an adjustable stop 21.

FIGURE 2 shows the top view of the front end of the roller arms. It is shown here in particular that the entry plate 22 located ahead of the deflector rolls 7 extends essentially over the entire Width of the belt wrapper, whereas the belts 13 and the deflector rolls 7 in the embodiment are distributed over two partial belts or partial rolls. The three guide rolls 15 are arranged to engage the sides of the belts and are located in a plane common to the guide elements 17 In operation the belt wrapper is shifted from a position to the right, as one views FIGURE 1, to a position against the rotating coiler drum 1. During the initial movement the tension cylinder 12 is subjected to a slight pressure to assure tautness of the belts and a control wheel 23 runs off the horizontal zone of a control track 24 at which time the bottom roller arm 6 is in its horizontal position. In the end zone of the movement of the control wheel, it runs along the ramplike portion of the control track and by means of a connecting rod raises the lower roller arms 6 until they run up against the adjustable stop 21. The stops 20 and 21 are purposely adjusted such that the distance between the guide elements 17 and 18 and the shell of the drum 1 exceeds the thickness of the material to be coiled; whereas, the distance between the body surfaces of the pinch rolls 15 and 16 on the one hand and the coiler drum on the other hand is less than the thickness of the material.

As the head end of the strip enters, it is guided at first between the entry plate 22 and the upper surface of the guide element 17 into the wedgelike gap formed between the belts 13 and the drum 1. At the end of this gap the pinch rolls 15 come into contact with the rolled material and urge it forcibly into the gap formed between the mandrel and the guide elements 17. At that moment the guide elements, due to the short distance of the strip leading end from the drum shell, i.e. with a relatively short lever arm, bend the strip leading end downwardly causing it to assume with the succeeding portion of the strip the curvature of the drum shell. The required heavy pressure forces are effected by the weight of the upper roller arms 4 and, in particular, by the belt tension engaging through the deflector and guide rolls 7 and 8. At the upper roller arms the belt tension has in the meantime been brought to its operating value through heavier action of the tension cylinder 12, and movement of the pinch rolls, which, due to the shorter lever arm, brings about increased contact forces against the strip. Through these increased contact forces alone, the feed strip is forced through the gap formed between the guide elements and mandrel; the use of a belt wrapper alone would not sutfice to urge the strip around the mandrel, because in the entry zone of the leading end of the strip, the belts run up tangentially and, therefore, are not able to exert normal forces.

After the initial permanent precurving of the material, the strip arrives beneath the entry guide elements 19, is advanced by the pinch rolls 16 and caused thereby to pass between the guide element 19 and the drum so that the first convolution is completed. At the end of a few additional revolutions, the strip is so firmly wound on the coiler drum 1 that the belt wrapper can be loosened and moved back to its starting position, thereby allowing the coiler drum to complete the winding operation.

The use of pinch rolls to assist the belt wrapper, as herein disclosed in connection with coilers for hot reduced strip, leads to a new combination in which the above-mentioned drawbacks of the known coilers are avoided. It also should be noted that the application of guide elements results in an extensive deformation which goes beyond that of the prior preshaping devices mounted ahead of the belt wrapper, because with the use of such means during the initial feeding of the coiler drum, permanent deformation takes place. It should be noted that the pinch rolls 15 and 16 are driven by means of guide and/or deflector rolls 8 and 9, respectively, connected with them by the common shafts. In the practice of the present invention, despite the heavy normal forces, which, if necessary, can still be increased further by drives, such as, hydraulic cylinders or the like, the entry of the leading end of the strip is relatively free from jerks through the presetting by means of the adjustable stops 20 and/or 21 of a gap that is purposely narrower than the thickness of the entering strip. Also, during entry of the strip front end the jerks or shocks directed against the belts can be avoided if, as illustrated only in FIGURE 2, the deflector rolls 7 are equipped with larger diameter guide rolls 26 extending through the belt plane. To the belt wrapper itself is assigned the task during the leadin of the strip to hold the rolled material in position on the drum and by bearing down to produce a frictional contact, which insures that the strip is carried along through friction after the initial convolution has been completed.

In accordance with the provisions of the patent statutes, we have explained the principles and operation of our invention and have illustrated and described what we consider to represent the best embodiment thereof. However, we desire to have it understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

We claim:

1. In a belt wrapper for preparing moving strip-like material for coiling on a reel or the like,

a frame adapted to be positioned adjacent said reel,

supporting members carried by said frame arranged so that a part of a belt supported by said members is caused to encircle at least a portion of the periphery of said reel and guide the material therearound,

the width of the belt with respect to the material is such that a portion of the material is left exposed while passing around said reel,

a pinch roll means carried by said frame arranged to present a portion of its periphery in the zone where the belt first contacts the reel so as to engage the exposed portion of the material in a manner to force the material against the reel, thereby to assist the belt in preparing the material for coiling on the reel.

2. In a belt wrapper according to claim 1, wherein said pinch roll means includes a first rotatably supported pinch roll adapted to engage the material as it enters the belt wrapper,

and a second rotatably supported pinch roll adapted to engage the material after it has been engaged by said first pinch roll.

3. In a belt wrapper according to claim 2, including at least two spaced-apart belts, said pinch rolls arranged between the belts and adapted to project past the belts in the direction of the reel.

4. In a belt wrapper according to claim 3 and with reference to the direction of rotation of the reel, including a first guide element arranged on the delivery side of said first pinch roll and a second guide element arranged on the entry side of said second pinch roll.

5. In a belt wrapper according to. claim 1, wherein said frame comprises a pair of upright members,

said support members comprise a pair of parallel shafts arranged between and perpendicular to said upright members,

said pinch roll means comprising at least two independent pinch rolls each rotatably carried by one of said shafts and spaced around the periphery of said reel,

a belt roll carried by each of said shafts arranged axially of said pinch rolls,

at least two belts carried by said belt rolls,

said pinch rolls being arranged between said 'belts and having diameters slightly larger than the diameters of the belt rolls.

6. In a belt wrapper according to claim 5, wherein the radius of the pinch roll exceeds the radius of thebelt rolls by the thickness of said belts.

7; In a belt wrapper according to claim 5, wherein said frame includes two displaceable arms, each of said arms adapted to carry a pinch roll and a belt roll.

8. In a belt wrapper according to claim 5, including a material guiding element arranged at the entry side of said second pinch roll.

9. In an apparatus according to claim 7, including separate adjustable stops carried by said frame engageable by said arms.

References Cited UNITED STATES PATENTS 2,792,996 5/1957 Lorig 72-148 2,890,008 6/1959 Jones 72148 2,981,493 4/1961 Maximilian 72148 3,228,225 1/1966 Hiegel 72-148 3,315,510 4/1967 Jones 72148 3,328,991 7/1967 Petros 72-148 MILTON S. MEHR, Primary Examiner. 

